City Of Garden Grove

PFAS monitoring results for a public water system in California

CA3010062UCMR 5EPA monitoring data
8.1Highest PFOA result, ppt
19Highest PFOS result, ppt
0.96Highest Hazard Index
775Results
PWSID
CA3010062
State
California
System type
community water system (CWS)
Population served
174,226
City
Garden Grove
Counties
Orange County
Primary source water
surface water (purchased)
UCMR 5 sampling
2023-03-14 to 2026-04-27 · 11 entry point(s) · water types: GW;SW
Service-area boundary
authoritative

PFOS ≥ 3 × its limit highest single result
PFOS ≥ 3 × its limit worst entry-point average

These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.

Water purchased from

Seller results are the seller's own entry-point samples, not measurements of this system's water. This system's own samples (below) may reflect purchased water, its own sources, or both.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)8.18.054
PFOS (ppt)1918.654
Hazard Index0.960.9251.0†

“<MRL” = every result for the compound was below its reporting limit. * Mean of all samples at each entry point with non-detects = 0 (EPA compliance convention; the Hazard Index also uses non-detects = 0); a screening comparison, not a formal running annual average. † Rescission proposed May 2026. PFOA/PFOS MCL 4 ppt (2024 NPDWR, in effect). PFHxS, PFNA, HFPO-DA (10 ppt each) and the Hazard Index (1.0) are 2024 NPDWR values; EPA proposed rescinding them on 18 May 2026 (comment period closed 20 Jul 2026).

Compared with California guidance levels

Highest single resultWorst entry-point average*California
PFHxS (ppt)9.69.253 (guidance)
PFOA (ppt)8.18.054 (guidance)
PFOS (ppt)1918.654 (guidance)
PFBS (ppt)00500 (guidance)
PFHxA (ppt)5.44.71,000 (guidance)

Sum standards add the listed compounds within each sample (non-detects = 0). State compliance is normally judged on averages over time; these are screening comparisons.

Sampling history

Sampled 2023-03-14 to 2026-04-27 · 11 entry point(s) · water types: GW;SW · 28 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-03-14MWD Intertie 1 (SW)SE1n/an/an/anone
2023-03-29MWD Intertie 1 (SW)SE1<4<40none
2023-06-21MWD Intertie 1 (SW)SE2<4<40lithium 19.76 µg/L
2023-09-13MWD Intertie 1 (SW)SE3<4<40lithium 34.75 µg/L
2023-10-24Well 20 (GW)SE1<4<40none
2023-10-24Well 21 Treatment Effluent (GW)SE1<4<40PFBA 6, PFHxA 4, PFPeA 8.2
2023-10-24Well 22 (GW)SE1<4<40PFBA 6.1, lithium 9.62 µg/L
2023-10-24Well 26 (GW)SE15.611.90.89none
2023-10-24Well 29 Treatment Finished Effluent (GW)SE1<4<40none
2023-10-24Well 30 Treatment Finished Effluent (GW)SE1<4<40PFPeA 7.5
2023-10-24Wells 23 & 28 Treatment (GW)SE1<4<40PFBA 8.8, lithium 10.82 µg/L
2023-12-06MWD Intertie 1 (SW)SE4<4<40lithium 30.34 µg/L
2024-04-24Well 21 Treatment Effluent (GW)SE2<4<40PFBA 6.5, PFHxA 5.4, PFPeA 8.6
2024-04-24Well 26 (GW)SE27.813.10.96PFHxA 3
2024-04-24Well 30 Treatment Finished Effluent (GW)SE2<4<40PFBA 5.2, PFPeA 8
2024-04-25Well 20 (GW)SE2<4<40none
2024-04-25Well 22 (GW)SE2<45.80.36PFBA 7.6
2024-04-25Well 29 Treatment Finished Effluent (GW)SE2<4<40PFPeA 4
2024-04-25Wells 23 & 28 Treatment (GW)SE2<4<40PFBA 14.6, PFPeA 3.4, lithium 9.9 µg/L
2024-10-23Well 27 (GW)SE28.1190.93PFHxA 3.8, PFPeA 3.2
2024-10-24Well 16 (GW)SE1<4<40none
2025-04-24Well 16 (GW)SE2<4<40none
2025-04-24Well 27 (GW)SE1818.30.87PFHxA 3.6, PFPeA 3.5
2025-07-28MWD Intertie 3 (SW)SE1<4<40none
2025-10-20MWD Intertie 3 (SW)SE2n/an/an/alithium 28.9 µg/L
2025-11-12MWD Intertie 3 (SW)SE2<4<40none
2026-01-27MWD Intertie 3 (SW)SE3<4<40lithium 35.03 µg/L
2026-04-27MWD Intertie 3 (SW)SE4<4<40none

“<4” = not detected at the reporting limit shown; “n/a” = not analyzed in that sample. Highlighted = at or above the 4 ppt MCL. HI computed per sample with non-detects as 0. Other detections lists every other quantified compound (lithium in µg/L).

All results by entry point

775 results. Each column is one sampling visit (date and UCMR 5 sample event). A number is a measured concentration; “< 4” = below the minimum reporting level shown; “–” = not analyzed in that visit. PFAS in ppt (ng/L); lithium in µg/L.

MWD Intertie 1 facility 91821 · sample point 3010062821 · surface water

CompoundMRL2023-03-14
SE1
2023-03-29
SE1
2023-06-21
SE2
2023-09-13
SE3
2023-12-06
SE4
11Cl-PF3OUdS5 ppt–< 5< 5< 5< 5
4:2 FTS3 ppt–< 3< 3< 3< 3
6:2 FTS5 ppt–< 5< 5< 5< 5
8:2 FTS5 ppt–< 5< 5< 5< 5
9Cl-PF3ONS2 ppt–< 2< 2< 2< 2
ADONA3 ppt–< 3< 3< 3< 3
HFPO-DA5 ppt–< 5< 5< 5< 5
NEtFOSAA5 ppt< 5–< 5< 5< 5
NFDHA20 ppt–< 20< 20< 20< 20
NMeFOSAA6 ppt< 6–< 6< 6< 6
PFBA5 ppt–< 5< 5< 5< 5
PFBS3 ppt–< 3< 3< 3< 3
PFDA3 ppt–< 3< 3< 3< 3
PFDoA3 ppt–< 3< 3< 3< 3
PFEESA3 ppt–< 3< 3< 3< 3
PFHpA3 ppt–< 3< 3< 3< 3
PFHpS3 ppt–< 3< 3< 3< 3
PFHxA3 ppt–< 3< 3< 3< 3
PFHxS3 ppt–< 3< 3< 3< 3
PFMBA3 ppt–< 3< 3< 3< 3
PFMPA4 ppt–< 4< 4< 4< 4
PFNA4 ppt–< 4< 4< 4< 4
PFOA4 ppt–< 4< 4< 4< 4
PFOS4 ppt–< 4< 4< 4< 4
PFPeA3 ppt–< 3< 3< 3< 3
PFPeS4 ppt–< 4< 4< 4< 4
PFTA8 ppt< 8–< 8< 8< 8
PFTrDA7 ppt< 7–< 7< 7< 7
PFUnA2 ppt–< 2< 2< 2< 2
lithium9 µg/L< 9–19.761734.749830.3433

MWD Intertie 3 facility 91816 · sample point 3010062816 · surface water

CompoundMRL2025-07-28
SE1
2025-10-20
SE2
2025-11-12
SE2
2026-01-27
SE3
2026-04-27
SE4
11Cl-PF3OUdS5 ppt< 5–< 5< 5< 5
4:2 FTS3 ppt< 3–< 3< 3< 3
6:2 FTS5 ppt< 5–< 5< 5< 5
8:2 FTS5 ppt< 5–< 5< 5< 5
9Cl-PF3ONS2 ppt< 2–< 2< 2< 2
ADONA3 ppt< 3–< 3< 3< 3
HFPO-DA5 ppt< 5–< 5< 5< 5
NEtFOSAA5 ppt–< 5–< 5< 5
NFDHA20 ppt< 20–< 20< 20< 20
NMeFOSAA6 ppt–< 6–< 6< 6
PFBA5 ppt< 5–< 5< 5< 5
PFBS3 ppt< 3–< 3< 3< 3
PFDA3 ppt< 3–< 3< 3< 3
PFDoA3 ppt< 3–< 3< 3< 3
PFEESA3 ppt< 3–< 3< 3< 3
PFHpA3 ppt< 3–< 3< 3< 3
PFHpS3 ppt< 3–< 3< 3< 3
PFHxA3 ppt< 3–< 3< 3< 3
PFHxS3 ppt< 3–< 3< 3< 3
PFMBA3 ppt< 3–< 3< 3< 3
PFMPA4 ppt< 4–< 4< 4< 4
PFNA4 ppt< 4–< 4< 4< 4
PFOA4 ppt< 4–< 4< 4< 4
PFOS4 ppt< 4–< 4< 4< 4
PFPeA3 ppt< 3–< 3< 3< 3
PFPeS4 ppt< 4–< 4< 4< 4
PFTA8 ppt–< 8–< 8< 8
PFTrDA7 ppt–< 7–< 7< 7
PFUnA2 ppt< 2–< 2< 2< 2
lithium9 µg/L< 928.9017–35.034–

Well 16 facility 91814 · sample point 3010062814 · groundwater

CompoundMRL2024-10-24
SE1
2025-04-24
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 20 facility 91802 · sample point 3010062802 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-25
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 21 Treatment Effluent facility 91822 · sample point 3010062822 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-24
SE2
PFBA5 ppt66.5
PFHxA3 ppt45.4
PFPeA3 ppt8.28.6
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 22 facility 91815 · sample point 3010062815 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-25
SE2
PFBA5 ppt6.17.6
PFHxS3 ppt< 33.6
PFOS4 ppt< 45.8
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L9.616< 9

Well 26 facility 91806 · sample point 3010062806 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-24
SE2
PFHxA3 ppt< 33
PFHxS3 ppt8.99.6
PFOA4 ppt5.67.8
PFOS4 ppt11.913.1
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 27 facility 91803 · sample point 3010062803 · groundwater

CompoundMRL2024-10-23
SE2
2025-04-24
SE1
PFHxA3 ppt3.83.6
PFHxS3 ppt9.38.7
PFOA4 ppt8.18
PFOS4 ppt1918.3
PFPeA3 ppt3.23.5
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 29 Treatment Finished Effluent facility 91824 · sample point 3010062824 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-25
SE2
PFPeA3 ppt< 34
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 30 Treatment Finished Effluent facility 91825 · sample point 3010062825 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-24
SE2
PFBA5 ppt< 55.2
PFPeA3 ppt7.58
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Wells 23 & 28 Treatment facility 91823 · sample point 3010062823 · groundwater

CompoundMRL2023-10-24
SE1
2024-04-25
SE2
PFBA5 ppt8.814.6
PFPeA3 ppt< 33.4
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L10.82389.897

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFPeA2631%8.6
2024-04-24
1.78–3.86<MRL3.488.2
lithium2532%35.03
2026-01-27
7.17–13.29<MRL9.930.3434.75
PFBA2627%14.6
2024-04-25
2.11–5.76<MRL5.27.68.8
PFHxA2619%5.4
2024-04-24
0.76–3.18<MRL<MRL3.84
PFHxS2619%9.6
2024-04-24
1.54–3.97<MRL<MRL8.99.3
PFOS2619%19
2024-10-23
2.62–5.85<MRL<MRL13.118.3
PFOA2615%8.1
2024-10-23
1.13–4.52<MRL<MRL7.88

Never detected (23): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFBS, PFDA, PFDoA, PFEESA, PFHpA, PFHpS, PFMBA, PFMPA, PFNA, PFPeS, PFTA, PFTrDA, PFUnA.

Left-censored Kaplan–Meier statistics (Helsel 2005; Helsel & Lee 2006, NADA for R). Units: ppt; lithium µg/L. Each compound has one reporting limit, so the Kaplan–Meier mean equals the upper mean bound (non-detects at the MRL); the lower bound sets non-detects to 0. “<MRL” = the percentile falls below the reporting limit and cannot be estimated. These describe this system's UCMR 5 samples, not population estimates.

Sources

  • EPA UCMR 5 occurrence data text files (UCMR5_All.txt; samples 2023-01-09 to 2026-06-17; data summary dated Jul 2026)
  • EPA SDWIS via ECHO SDWA downloads, quarter 2026Q3
  • EPA Public Water System Service Areas v3 (Mar 2026)
  • US Census Bureau cartographic boundary counties 1:500k, 2024
  • EPA/USGS NHDPlus V2 (medium resolution) flowlines, Strahler order 2+

Data build 90f0922cd84f · 2026-10-18T04:12Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.